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HMRC internal manual

Compliance Operational Guidance

Supporting Guidance: employer compliance: guidance by subject: settlement: procedure to be used when a NPS account cannot be traced

Calculating NICs Where There Is No Trace of a NPS Account

If a NPS account cannot be traced for a director or employee (for example, the full identity details may not be known) NIRS Calc Support can still be used. However, any calculation will have to take into account details from the employer’s records of any NICs already paid rather than any details held on NPS.

If the employer cannot provide any details of NICs already paid, then assume that none has been paid for the relevant pay period.